Final answer:
The car with larger inertia moves slower than the car with smaller inertia when both are pushed with the same force. If both cars have the same inertia, they will move at the same speed after being pushed. The total momentum of a system is conserved during collisions in the absence of external forces.
Step-by-step explanation:
The speed at which the two metal cars move after being pushed depends on their inertia. Inertia is the property of matter that causes it to resist changes in its state of motion. The greater the inertia (which is directly related to mass), the less it will accelerate under a given force. According to Newton's second law of motion, the acceleration of an object is directly proportional to the net force acting upon it and is inversely proportional to its mass (Force = mass × acceleration).
a) If the inertia of one car is larger than the other, then the car with larger inertia will move slower than the car with smaller inertia when both are pushed with the same force. This is because the larger inertia (mass) requires more force to achieve the same acceleration as the car with smaller inertia.
b) If the inertia of both cars is the same, they will move at the same speed after being pushed with the same amount of force, since acceleration will be the same for both vehicles.
Applying this to collisions, the total momentum of a system is conserved in the absence of external forces. If two cars collide, the momentum lost by one will be gained by the other, but the total system momentum remains constant if no external forces are acting.